1. Field of the Invention
This invention relates to a support leg device preferred to be used for cases of an audio equipment such as an audio system or the like, or various information equipment.
2. Detailed Description of the Prior Art
Conventionally, for example, a disk player, which reproduces sound by driving an optical disk abbreviated to CD (compact disk) or DVD (digital versatile disk), is provided with a power source for rotationally driving the disk, therefore, the inside of the equipment is excited to oscillate and resonance occurs. Moreover, since such an audio equipment is generally set up on a rack like an audio rack or the like, the rack is excited by external causes in the room or the reproduced sound, and the vibration is transmitted to the equipment internals.
However, an optical disk is provided with a minute continuous track formed thereon, and the track is read by being irradiated with laser light from a servo-controlled optical pickup. Therefore, this optical pickup is arranged so as to drive the disk by accurately following up even a minute servo signal, and for this purpose, the optical pickup has a supported construction so as to be easy to move in the directions of tracking and focusing.
Due to such a structural feature, even a slight shake of the optical pickup caused by vibration transmitted from a driving source of the optical disk or the outside of the equipment causes a pit reading error of the optical pickup, namely, it causes a pit loss to deteriorate an audio reproduction characteristic.
Therefore, as a means, what is called a means for mechanical earthing, for absorbing and cutting off the vibrations, a combination of elastic bodies such as a coil spring or rubber as support legs of the equipment case is generally adopted, however in the case of such a combined construction, the support legs are secured to the bottom plate of the equipment case by screws. Therefore, the fitting strength of the support legs is limited by the rigidity of the screw, and the mechanical earthing has not sufficiently been obtainable. As a means for solving such a problem, it has been confirmed that the case is effectively supported at three or four points by using spike legs in contact with the rack at a single point, respectively.
This arrangement is such one that for example, as shown in FIG. 5, a leg pillar L1 of a support leg main body L secured to an audio equipment A such as a disk player is formed like a conic spike shape so that its spiry point is grounded on the top plate surface of the rack B, and normally, a stand base S is to be interposed between the leg pillar L1 and the rack after setting up of the audio equipment. Moreover, in order to absorb and cut off the vibrations more effectively, there is a tendency to increase the sharpness of the leg pillar L2 as shown in FIG. 6.